Purulent Flexor Tendon Rupture of the Hand due to Mycobacterium abscessus Infection: A Case Report and Review of the Literature.

Mycobacterium abscessus infection of the upper extremities is uncommon. However, M abscessus can cause severe chronic tenosynovitis, and delayed diagnosis may result in poor outcomes. We describe an unusual clinical case of purulent flexor tendon synovitis followed by subcutaneous tendon rupture due to M abscessus infection in a patient with diabetes mellitus. A 76-year-old man presented to our hospital with painful, erythematous swelling over his left fourth finger. On physical examination, the left fourth finger was swollen and reddish, with persistent exudate from the surgical scar. The left elbow was also swollen and reddish with persistent discharge, which was consistent with olecranon bursitis. The patient was unable to flex his left fourth finger, and the passive range of motion of the finger was also restricted. The physical examination findings and patient history suggested purulent flexor tendinitis. His infection healed after radical debridement of necrotic tissue and administration of antibiotics effective against M abscessus. Third-stage flexor reconstruction restored the function of the fourth finger. The combination of surgical debridement and chemotherapy was the most effective treatment for mycobacterial tenosynovitis. This case shows that M abscessus can cause chronic severe purulent tenosynovitis and flexor tendon rupture after tendon surgery. Although early diagnosis and combination treatment with debridement and chemotherapy might improve outcomes by limiting the severity and duration of damage to the flexor synovial system, late-presenting patients require combined radical debridement of necrotic tissue and aggressive chemotherapy followed by staged flexor tendon reconstruction.